Field of the Invention
This invention relates to oil filters for internal combustion engines and more particularly to systems for oil filter holders providing improved installation and removal mechanisms.
Search of the prior art revealed the following U.S. Pats. Nos. 3,950,251; 2,877,903. These inventions do not provide the advantages of the instant invention. Certain oil filters of the prior art have a dismountable outer cover. This cover may be removed and the filter element therein replaced. The cover is then replaced and fastened tightly with a fresh gasket in place for sealing. Sealing the cover oil tight generally involves tightening a bolt or screw to a prescribed torque to compress the gasket. And the gasket and sealing surfaces must be lubricated to ensure a reproducible degree of tightness. A totally replaceable "spin-on" filter with integral cover in popular use screws onto a threaded pipe projecting from a sealing plate. The degree of tightness of screwing onto the pipe is critical to ensure compressing a gasket against the sealing plate sufficiently to prevent loss of oil and subsequent destruction of the engine. Furthermore, if the filter is overtightened, it may be difficult to remove after use, requiring a special wrench. Furthermore, if the filter is not correctly positioned at installation, the threads may be crossed, stripping them, or giving an incorrect indication of tightness, resulting in oil loss.